Voters register at a polling station in Seoul, Dec. 19, 2012. Polls opened early Wednesday morning in South Korea's closely contested presidential election, which pits the daughter of a military strongman against a former human rights lawyer once jailed for protesting his rule. (Xinhua/Park Jin-hee)

A voter casts his ballot at a polling station in Seoul, Dec. 19, 2012. Polls opened early Wednesday morning in South Korea's closely contested presidential election, which pits the daughter of a military strongman against a former human rights lawyer once jailed for protesting his rule. (Xinhua/Park Jin-hee)

A voter casts her ballot at a polling station in Seoul, Dec. 19, 2012. Polls opened early Wednesday morning in South Korea's closely contested presidential election, which pits the daughter of a military strongman against a former human rights lawyer once jailed for protesting his rule. (Xinhua/Park Jin-hee)

A voter enters a booth to fill his ballot at a polling station in Seoul, Dec. 19, 2012. Polls opened early Wednesday morning in South Korea's closely contested presidential election, which pits the daughter of a military strongman against a former human rights lawyer once jailed for protesting his rule. (Xinhua/Park Jin-hee)

Voters fill their ballots at a polling station in Seoul, Dec. 19, 2012. Polls opened early Wednesday morning in South Korea's closely contested presidential election, which pits the daughter of a military strongman against a former human rights lawyer once jailed for protesting his rule. (Xinhua/Park Jin-hee)

Moon Jae-in, South Korean presidential candidate of the center-left main opposition Democratic United Party, prepares to cast his ballot at a polling station in Pusan, Dec. 19, 2012. Polls opened early Wednesday morning in South Korea's closely contested presidential election, which pits the daughter of a military strongman against a former human rights lawyer once jailed for protesting his rule. (Xinhua)

Moon Jae-in, South Korean presidential candidate of the center-left main opposition Democratic United Party, prepares to cast his ballot with his wife at a polling station in Pusan, Dec. 19, 2012. Polls opened early Wednesday morning in South Korea's closely contested presidential election, which pits the daughter of a military strongman against a former human rights lawyer once jailed for protesting his rule. (Xinhua)

A voter casts her ballot at a polling station in Seoul, Dec. 19, 2012. Polls opened early Wednesday morning in South Korea's closely contested presidential election, which pits the daughter of a military strongman against a former human rights lawyer once jailed for protesting his rule. (Xinhua/Park Jin-hee)

Park Geun-hye, South Korean presidential candidate of the conservative ruling Saenuri Party, casts her ballot at a polling station in Seoul, Dec. 19, 2012. Polls opened early Wednesday morning in South Korea's closely contested presidential election, which pits the daughter of a military strongman against a former human rights lawyer once jailed for protesting his rule. (Xinhua/Park Jin-hee)

Park Geun-hye (C), South Korean presidential candidate of the conservative ruling Saenuri Party, speaks to the media after casting her ballot at a polling station in Seoul, Dec. 19, 2012. Polls opened early Wednesday morning in South Korea's closely contested presidential election, which pits the daughter of a military strongman against a former human rights lawyer once jailed for protesting his rule. (Xinhua/Park Jin-hee)

Park Geun-hye (front), South Korean presidential candidate of the conservative ruling Saenuri Party, speaks to the media after casting her ballot at a polling station in Seoul, Dec. 19, 2012.  Polls opened early Wednesday morning in South Korea's closely contested presidential election, which pits the daughter of a military strongman against a former human rights lawyer once jailed for protesting his rule. (Xinhua/Park Jin-hee)